TWI388625B - Aromatic polycarbonate resin composition and light-diffusing formed body - Google Patents

Description

Aromatic polycarbonate resin composition and light diffusion molded article

The present invention relates to an aromatic polycarbonate resin composition and a light diffusion molded article.

A molded article made of an aromatic polycarbonate resin can be used for electrical purposes because of its transparency, impact resistance, heat resistance, dimensional stability, and self-ignition property (flammability). electronic. OA machines, optical parts, precision machinery, locomotives, security. Medical, building materials, groceries and other fields. In addition, a light-diffusing molded article comprising a resin composition of a light-diffusing agent such as inorganic fine particles or polymer fine particles is added to the aromatic polycarbonate-based resin, and is compared with a light-diffusing molded article composed of an acrylic resin. It is excellent in heat resistance and dimensional stability, and thus can be used for a lamp cover, a meter, a kanban (especially an interior), a resin window glass, an image reading device, or a light diffusing plate for an image display device (for example) , a light diffusing plate for a backlight module such as a liquid crystal display device, a light diffusing plate for projecting a display screen such as a television, etc.), a light diffusing film (for example, for improving the brightness of a liquid crystal display device, etc.) In a wide range of fields such as a transparent light-diffusing film.

A resin which is a light-diffusing agent such as calcium carbonate, barium sulfate, cerium oxide or titanium oxide added to an aromatic polycarbonate resin as an aromatic polycarbonate resin composition for a light-diffusing molded article material The composition (Patent Document 1), a resin composition in which a partially crosslinked polymer fine particle is added to an aromatic polycarbonate resin (Patent Document 2), and a non-melting propylene polymer fine particle, titanium oxide, and tantalum A resin composition in which a compound is added to an aromatic polycarbonate resin (Patent Documents 3 and 4).

In recent years, with the increase in size, thickness (light weight), shape complication, and high performance of image display devices, light-diffusing molded articles, particularly light-diffusing sheets used in image display devices, In order to increase the size, thickness, weight, and shape of the light-diffusing film, an aromatic polycarbonate-based resin composition having excellent formability (melt flowability) is being sought. . Further, in the light-diffusing molded article, surface treatment such as matting property by printing or the like is required, and it is required to improve the chemical resistance and the like.

However, in general, since the aromatic polycarbonate resin is amorphous, it has a problem that the molding processing temperature is high and the melt fluidity is poor, and the chemical resistance is poor.

As a method of improving the melt fluidity of the aromatic polycarbonate-based resin composition, (1) a method of lowering the molecular weight of the aromatic polycarbonate-based resin itself as a matrix resin is known. Further, (2) a method of improving the melt fluidity by polymerizing an aromatic polycarbonate-based resin with a specific styrene-based resin to form a melt enthalpy (for example, Patent Documents 5 and 6); A method of improving the melt fluidity by polymerizing an aromatic polycarbonate-based resin with a specific methacrylate-based resin to entangle the polymer (for example, Patent Document 7). Further, in order to improve the melt fluidity of the aromatic polycarbonate-based resin composition, (4) a method of adding a polyester oligomer (for example, Patent Document 8), and (5) adding a polycarbonate oligomer A method of a polymer (Patent Document 9), (6) A method of adding a low molecular weight styrene copolymer (for example, Patent Documents 10 to 12).

However, in these prior methods, although the melt fluidity can be improved to some extent, the following problems still exist.

Although the method of (1) can greatly improve the melt fluidity, if the excessive molecular weight is lowered, the heat resistance, chemical resistance, and impact resistance of the molded article composed of the aromatic polycarbonate resin are impaired. Therefore, in order to continue to maintain the excellent properties of the molded article, there is still a limitation in the method of increasing the melt fluidity of the aromatic polycarbonate-based resin composition by lowering the molecular weight of the aromatic polycarbonate-based resin.

In the methods (2) and (3), the balance between the peeling resistance of the molded article and the melt fluidity of the aromatic polycarbonate-based resin composition is not sufficient. Specifically, in the method of (2), the aromatic polycarbonate resin composition is excellent in melt fluidity, but the compatibility is insufficient, so that the surface layer is easily peeled off on the molded article, and the appearance is greatly reduced. And mechanical properties. In the method (3), the aromatic polycarbonate resin composition is excellent in compatibility, and the transparency of the molded article is good, but the effect of improving the melt fluidity of the aromatic polycarbonate resin composition is small. Therefore, in order to improve the melt fluidity, it is necessary to increase the amount of the methacrylate resin to maintain the heat resistance and impact resistance of the molded article, and to improve the melt fluidity of the aromatic polycarbonate resin composition. Still has limitations.

The method of (4) and (5) can effectively improve the melt fluidity of the aromatic polycarbonate-based resin composition, but there is a problem that the heat resistance and impact resistance of the molded article are remarkably lowered.

In the method of (6), the low-molecular weight styrene-based copolymer is added in a small amount, and in order to maintain the heat resistance of the molded article to some extent, the melt fluidity of the aromatic polycarbonate-based resin composition can be improved. However, the compatibility is still insufficient. Therefore, the surface layer is liable to be peeled off on the molded article, and there is still a problem that the impact strength, the welding appearance which is important in actual use, and the front impact are insufficient.

As described above, in any of the prior methods, the melt flowability of the aromatic polycarbonate resin-based composition can be improved without impairing the excellent properties of the molded article composed of the aromatic polycarbonate resin-based composition. The drug resistance and other aspects are not sufficient.

[Patent Document 1] Japanese Patent Publication No. Sho 57-24186.

[Patent Document 2] Japanese Patent Laid-Open No. Hei 3-143950.

[Patent Document 3] Japanese Patent Laid-Open No. Hei 10-17761.

[Patent Document 4] Japanese Laid-Open Patent Publication No. 2005-298710.

[Patent Document 5] Japanese Patent Publication No. Sho 59-42024.

[Patent Document 6] Japanese Laid-Open Patent Publication No. SHO 62-138514.

[Patent Document 7] Japanese Patent No. 2622152.

[Patent Document 8] Japanese Patent Publication No. Sho 54-37977.

[Patent Document 9] Japanese Patent Laid-Open No. Hei 3-24501.

[Patent Document 10] Japanese Patent Publication No. Sho 52-784.

[Patent Document 11] Japanese Laid-Open Patent Publication No. Hei 11-181197.

[Patent Document 12] Japanese Patent Laid-Open Publication No. 2000-239477.

An object of the present invention is to provide an aromatic polycarbonate resin composition and a light diffusion molded article. The aromatic polycarbonate resin composition does not impair the excellent properties (light diffusibility, heat resistance, impact resistance, dimensional stability, and the like) of the obtained light-diffusing molded article, and can improve melt fluidity (formability). And the drug resistance; the light-diffusing molded article has excellent light diffusibility, heat resistance, impact resistance, dimensional stability, and chemical resistance, and can be increased in size, thickness (light weight), shape complexity, and high Performance.

The aromatic polycarbonate-based resin composition of the present invention is characterized in that an aromatic carbonate-based resin (A), a fluidity improver (B), and a light-diffusing agent (C) are added; and the fluidity improver ( B) is a monomer (b2) represented by the following formula (I) and 50 to 40% by mass of the aromatic vinyl monomer (b1), 0.5 to 50% by mass, and other monomers of 0 to 40% by mass. The polymer obtained by the monomer mixture of the body (b3), wherein the total of the monomer (b1) to the monomer (b3) is 100% by mass.

In the formula (I), R ¹ is a hydrogen atom or a methyl group, and R ² is a phenyl group which may have a substituent.

Moreover, the light-diffusing molded article of the present invention is formed by molding the aromatic polycarbonate-based resin composition of the present invention.

The aromatic polycarbonate-based resin composition of the present invention does not impair the excellent properties (light diffusibility, heat resistance, impact resistance, dimensional stability, etc.) of the obtained light-diffusing molded article, and is compared with a conventional one. It has excellent melt fluidity (formability) and chemical resistance.

Further, the light-diffusing molded article of the present invention has excellent light diffusibility, heat resistance, impact resistance, dimensional stability, chemical resistance, and the like, and can be increased in size, thickness (light weight), and complicated in shape. And high performance.

The above and other objects, features and advantages of the present invention will become more <RTIgt;

[Aromatic polycarbonate resin (A)]

The aromatic polycarbonate resin (A) is an aromatic polycarbonate polymer or copolymer obtained by reacting an aromatic hydroxy compound with a carbonic acid diester such as diphenyl carbonate or phosgene. The aromatic polycarbonate resin (A) may also be branched. In the case of the branched aromatic polycarbonate-based resin (A), an aromatic dihydroxy compound, an aromatic polyhydroxy compound, or the like can be used in combination as the aromatic hydroxy compound.

Examples of the aromatic dihydroxy compound include 2,2-bis(4-hydroxyphenyl)propane (=bisphenol A), tetramethylbisphenol A, and bis(4-hydroxyphenyl)-p-diiso. Propyl benzene, hydroquinone, resorcinol, and 4,4-dihydroxydiphenyl. Among them, preferred is bisphenol A. Further, for the purpose of improving flame retardancy, these aromatic dihydroxy compounds may have a structure substituted with a tetraalkylphosphine sulfonate, a bromine atom, or a group having a decane structure.

As the aromatic polyhydroxy compound, for example, phloroglucinol, 4,6-dimethyl-2,4,6-tris(4-hydroxyphenyl)heptene-2, 4,6-dimethyl group can be mentioned. -2,4,6-tris(4-hydroxyphenyl)heptane, 2,6-dimethyl-2,4,6-tris(4-hydroxyphenyl)heptene-3, 1,3,5 - Tris(4-hydroxyphenyl)benzene and 1,1,1-tris(4-hydroxyphenyl)ethane and the like. The aromatic polyhydroxy compound used in the case of obtaining the branched aromatic polycarbonate-based resin (A) is preferably used in an amount of 0.01 to 10 mol per mol of the aromatic dihydroxy compound (100 mol%). %, better is 0.1~2 mole%.

For the purpose of adjusting the molecular weight of the aromatic polycarbonate-based resin (A) and adjusting the terminal group, a monovalent aromatic hydroxy compound or a monovalent aromatic hydroxy compound derivative such as a chloroform may be used. Examples of the monovalent aromatic hydroxy compound and derivatives thereof include alkylphenols such as phenol, m-cresol, p-cresol, p-propylphenol, p-tert-butylphenol, and p-tert-butyl substituted phenol, and the like. These derivatives and the like. The amount of these monovalent aromatic hydroxy compounds and/or derivatives thereof is usually 0.1 to 10 mol%, preferably 1 to 8 mol%, based on the aromatic dihydroxy compound (100 mol%). .

For the purpose of improving flame retardancy, the aromatic polycarbonate-based resin (A) may also copolymerize a polymer or oligomer having a decane structure; or for the purpose of improving melt fluidity during molding, A derivative such as a dicarboxylic acid or a dicarboxylic acid chloride can be copolymerized.

The molecular weight of the aromatic polycarbonate-based resin (A), in view of obtaining a resin composition having high fluidity, can be converted to a viscosity average based on the viscosity of the solution measured at a temperature of 25 ° C using ethylene chloride as a solvent. The molecular weight is preferably from 12,000 to 40,000, more preferably from 12,000 to 25,000, and particularly preferably from 12,000 to 18,000. Further, two or more kinds of aromatic polycarbonate-based resins (A) may be used in combination.

As the resin material containing the aromatic polycarbonate-based resin (A), an aromatic polycarbonate-based polymer aryl fluorene in which an aromatic polycarbonate-based resin (A) is mixed with another resin or an elastomer described below can also be used. ester.

[Other resins or elastomers]

The aromatic polycarbonate-based resin composition does not impair the excellent transparency, impact resistance, heat resistance, dimensional stability, and self-ignition property (flammability) inherent in the aromatic polycarbonate-based resin (A). In the range of 50 parts by mass or less and 50 parts by mass or less based on 100 parts by mass of the aromatic polycarbonate-based resin (A), other resins or elastomers may be added.

Examples of the other resin include polystyrene (PSt), a styrene-based random copolymer (acrylonitrile-styrene resin (AS resin), etc.), an interpolymer of styrene and maleic anhydride, and graft copolymerization. (acrylonitrile-butadiene-styrene resin (ABS resin), acrylonitrile-ethylene propylene rubber-styrene resin (AES resin), acrylonitrile-acrylate-styrene resin (AAS resin), high impact copolymerization a styrene resin such as styrene (HIPS) or the like; a polyethylene terephthalate (PET), a polybutylene terephthalate (PBT), a polyester such as these copolymers, or a polymethyl group; Acrylic resin such as methyl acrylate (PMMA), a copolymer having a methyl methacrylate unit, or an olefin resin such as polypropylene (PP), polyethylene (PE) or ethylene-(meth)acrylate copolymer Polyurethane; anthrone resin; syndiotactic PS; 6-nylon, 6,6-nylon, etc. polyamine; polyaryl ester; polyphenyl sulfide; polyether ketone; polyfluorene; Polyamide, imidaldehyde, etc., various general-purpose resins or engineering plastics.

Examples of the elastomer include isobutylene-isoprene rubber; polyester elastomer; styrene-butadiene rubber, polystyrene-polybutadiene-polystyrene (SBS), and polystyrene- Poly(ethylene-butylene)-polystyrene (SEBS), polystyrene-polyisoprene-polystyrene (SIS), polystyrene-poly(ethylene-propylene)-polystyrene (SEPS), etc. a styrene-based elastomer; a polyolefin-based elastomer such as an ethylene-propylene rubber; a polyamide-based elastomer; an acrylic elastomer; and a diene rubber, an acrylic rubber, an anthrone rubber, etc. A core-shell type impact resistance improver represented by methyl acrylate-butadiene-styrene resin (MBS resin), methyl methacrylate-acrylonitrile-styrene resin (MAS resin).

[Liquidity improver (B)]

The fluidity improver (B) is a monomer (b2) of the following formula (I) and a mass of 0 to 40 which are polymerized from 0.5 to 99.5% by mass of the aromatic vinyl monomer (b1) and from 0.5 to 99.5% by mass. A monomer mixture composed of % of the other monomers (b3) (wherein the monomers (b1) to (b3) are 100% by mass in total. The polymer obtained.

(In the formula (I), R ¹ is a hydrogen atom or a methyl group, and R ² may be a phenyl group having a substituent.)

The fluidity improver (B) exhibits a phase separation behavior with the aromatic polycarbonate-based resin (A) during melt molding, and has excellent peeling resistance in the use temperature region of the light-diffusing molded article. The level of compatibility (affinity) with the aromatic polycarbonate resin (A) is exhibited, so that the properties (heat resistance, impact resistance, etc.) of the aromatic polycarbonate resin (A) are not impaired. Therefore, it exhibits an effect that the melt fluidity (formability) and the chemical resistance can be remarkably improved.

The fluidity improver (B) preferably has a mixing ratio (% by mass) of each monomer in the monomer mixture before polymerization and a content (% by mass) of each monomer constituent unit in the polymer after polymerization. In order to obtain such a polymer, it is preferred that the polymerization ratio of the monomer mixture is 90% by mass or more, more preferably 95% by mass or more, particularly preferably 97% by mass or more. When the polymerization rate is 90% by mass or more, the mixing ratio (% by mass) of each monomer in the monomer mixture before polymerization substantially coincides with the content (% by mass) of each monomer constituent unit in the polymer after polymerization. When the polymerization rate is less than 90% by mass, the mixing ratio (% by mass) of each monomer in the monomer mixture may be different from the content (% by mass) of the monomer constituent unit contained in the polymer after polymerization.

Examples of the aromatic vinyl monomer (b1) include styrene, α-methylstyrene, p-methylstyrene, p-tert-butylstyrene, p-methoxystyrene, and o-methoxy group. Styrene, 2,4-dimethylstyrene, chlorinated styrene, brominated styrene, vinyl toluene, vinyl naphthalene, and vinyl anthracene. These may be used alone or in combination of two or more. Among them, preferred are styrene, α-methylstyrene, and p-tert-butylstyrene.

The content of the aromatic vinyl monomer (b1) is from 0.5 to 99.5% by mass in the monomer mixture (100% by mass). When the content of the aromatic vinyl monomer (b1) is in this range, the fluidity improver (B) can exhibit excellent melt fluidity and an effect of improving drug resistance.

When the content of the aromatic vinyl monomer (b1) exceeds 99.5% by mass, the compatibility with the aromatic polycarbonate resin (A) is insufficient, and as a result, the light-diffusing molded article is peeled off in a layered manner. Will impair the appearance and mechanical properties. When the content of the aromatic vinyl monomer (b1) is less than 0.5% by mass, the compatibility with the aromatic polycarbonate resin (A) is excessively high, and the phase separation behavior during melting may not be sufficiently exhibited, and may be lowered. The effect of improving the fluidity of the melt, and may reduce the effect of improving the drug resistance.

The content of the aromatic vinyl monomer (b1) is preferably less than or equal to 98% by mass, more preferably less than or equal to 96, in view of the balance between appearance and mechanical properties and melt fluidity and drug resistance. The mass%, particularly preferably, is less than or equal to 93% by mass, particularly preferably less than or equal to 90% by mass. Further, the content of the aromatic vinyl monomer (b1) is preferably 10% by mass or more, more preferably 20% by mass or more, particularly preferably 50% by mass or more, particularly preferably It is greater than or equal to 70% by mass.

Examples of the monomer (b2) represented by the formula (I) include phenyl (meth)acrylate, 4-t-butylphenyl (meth)acrylate, and bromophenyl (meth)acrylate. Dibromophenyl (meth)acrylate, 2,4,6-tribromophenyl (meth)acrylate, monochlorophenyl (meth)acrylate, dichlorophenyl (meth)acrylate, and (methyl) Trichlorophenyl acrylate and the like. These may be used alone or in combination of two or more. Among them, particularly preferred is phenyl (meth)acrylate. In the present invention, "(meth)acrylic acid" means acrylic acid and/or methacrylic acid.

The content of the monomer (b2) is from 0.5 to 99.5% by mass in the monomer mixture (100% by mass). When the content of the monomer (b2) is in this range, the fluidity improver (B) exhibits an excellent effect of improving compatibility (peeling resistance).

When the content of the monomer (b2) is less than 0.5% by mass, the compatibility with the aromatic polycarbonate-based resin (A) is insufficient, and as a result, the light-diffusing molded article is peeled off in a layered manner, which may impair appearance and machinery. characteristic. When the content of the monomer (b2) exceeds 99.5% by mass, the compatibility with the aromatic polycarbonate resin (A) is excessively high, and the phase separation behavior during melting is not sufficiently exhibited, and the melt fluidity may be lowered. The effect, and may reduce the improvement of drug resistance.

The content of the monomer (b2) is preferably less than or equal to 90% by mass, more preferably less than or equal to 80% by mass, especially in view of the appearance and the balance of mechanical properties and melt fluidity and drug resistance. Preferably, it is 50% by mass or less, and particularly preferably 30% by mass or less. Further, the monomer (b2) content is preferably greater than or equal to 2% by mass, more preferably greater than or equal to 4% by mass, particularly preferably greater than or equal to 7% by mass, particularly preferably greater than or equal to 10% by mass.

The polymer constituting the fluidity improver (B) may contain 0 to 40% by mass of the aromatic vinyl monomer (b1) and the monomer (b2), if it does not impair the above characteristics. ) other monomers (b3) copolymerized.

The other monomer (b3) is an α,β-unsaturated monomer. As such a monomer, for example, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl acrylate, and lauryl (meth)acrylate may be mentioned. , stearyl (meth) acrylate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate, tert-butyl (meth) acrylate, isobornyl (meth) acrylate, (methyl) An alkyl (meth)acrylate such as t-butylcyclohexyl acrylate; (meth)acrylic acid, 2-hydroxyethyl (meth)acrylate, glycidyl (meth)acrylate, terephthalic acid a (meth) acrylate having a reactive functional group such as 2-methacrylic acid methoxyethyl ester, (meth)acrylic acid allyl ester or 1,3-butene dimethacrylate; benzoic acid ethylene Ester, vinyl acetate, maleic anhydride, n-phenylmaleimide, cyclohexylmaleimide, divinylbenzene, and the like. These may be used alone or in combination of two or more.

The content of the other monomer (b3) is 0 to 40% by mass in the monomer mixture (100% by mass). When the content of the monomer (b3) exceeds 40% by mass, the effect of improving the melt fluidity and the chemical resistance of the aromatic polycarbonate-based resin composition may be lowered. The content of the other monomer (b3) is preferably less than or equal to 30% by mass, more preferably less than or equal to 20% by mass, particularly preferably less than or equal to 10% by mass, particularly preferably less than or equal to 5 mass%.

Since the compatibility between the fluidity improving agent (B) and the aromatic polycarbonate resin (A) is excellent, the light diffusion is composed of the aromatic polycarbonate resin composition containing the fluidity improving agent (B). The total light transmittance of the molded article will become higher. The two components of the aromatic vinyl monomer (b1) and the monomer (b2) represented by the formula (I) are used as the polymer constituting the fluidity improver (B), and the content of these components is set to a specific range. Therefore, the total light transmittance can be further improved.

The polymer which can further increase the total light transmittance of the molded article includes, for example, the following two types: an aromatic vinyl monomer (b1) of from 0.5 to 40% by mass and a monomer of from 60 to 99.5% by mass. B2) a monomer mixture (wherein (b1) and (b2) are 100% by mass in total) to obtain a polymer (B1); and a polymerization of 60 to 99.5% by mass of an aromatic vinyl monomer (b1) a polymer (B2) obtained by mixing a monomer mixture of 0.5 to 40% by mass of the monomer (b2) (wherein (b1) and (b2) are 100% by mass in total).

The mass average molecular weight of the polymer constituting the fluidity improver (B) is preferably from 5,000 to 200,000. When the mass average molecular weight is less than 5,000, the amount of the low molecular weight substance is relatively increased, and various properties such as heat resistance and rigidity may be lowered. Further, there is a high possibility that the appearance of molded articles such as smoke, mist, mechanical contamination, fisheye spots, and silvering during melt forming is poor. When a light-diffusing molded article having a high total light transmittance at a high temperature (a light-diffusing molded article having a small temperature dependence of haze) is required, the mass average molecular weight of the polymer can be high. Therefore, the mass average molecular weight of the polymer is preferably 10,000 or more, more preferably 15,000 or more, particularly preferably 30,000 or more, particularly preferably 40,000 or more.

In addition, when the mass average molecular weight of the polymer exceeds 200,000, the melt viscosity of the aromatic polycarbonate-based resin composition may also become high, and the effect of improving the melt fluidity may not be obtained. Furthermore, in the case where it is desired to improve only the drug resistance, there is no problem even if the mass average molecular weight of the polymer exceeds 200,000. In the case where a significant effect of improving the melt fluidity is required, the mass average molecular weight of the polymer is preferably low. Therefore, the mass average molecular weight of the polymer is preferably less than or equal to 170,000, more preferably less than or equal to 150,000, still more preferably less than or equal to 120,000, particularly preferably less than or equal to 100,000.

The molecular weight distribution of the polymer constituting the fluidity improver (B), that is, the mass average molecular weight (Mw) / number average molecular weight (Mn) is preferably small. The molecular weight distribution is preferably less than or equal to 4.0, more preferably less than or equal to 3.0, and particularly preferably less than or equal to 2.0. When the molecular weight distribution exceeds 4.0, the melt viscosity of the aromatic polycarbonate-based resin composition may also become high, and the effect of improving the melt fluidity may not be obtained.

Examples of the method for producing the polymer constituting the fluidity improver (B) include an emulsion polymerization method, a suspension polymerization method, a solution polymerization method, and a bulk polymerization method. Among them, in view of the ease of the recovery method, a suspension polymerization method or an emulsion polymerization method is preferred. Further, in the case of the emulsion polymerization method, there is a possibility that the residual salt in the polymer causes thermal decomposition of the aromatic polycarbonate-based resin. Therefore, in the case of emulsion polymerization, it is preferred to use a carboxylate emulsifier or the like to recover a solidified polymer to be recovered, or to use a calcium ion salt or the like by using a nonionic anionic emulsifier such as a phosphate ester or the like. The solidified polymer is salted out and recovered.

The amount of addition of the fluidity improver (B) can be appropriately determined depending on the desired physical properties and the like. In order to reduce the characteristics (light diffusibility, heat resistance, impact resistance, etc.) of the light-diffusing molded article, effective melt fluidity and an effect of improving drug resistance are obtained, and the amount of the fluidity improver (B) is added. It is preferably 0.1 to 30 parts by mass based on 100 parts by mass of the total of the aromatic polycarbonate resin (A) and the other resin and/or elastomer. When the amount of the fluidity improving agent (B) added is less than 0.1 part by mass, sufficient melt fluidity and an effect of improving the chemical resistance may not be obtained. When the amount of the fluidity improver (B) added exceeds 30 parts by mass, the excellent properties of the light-diffusing molded article may be impaired. The addition amount of the fluidity improver (B) is preferably 1 part by mass or more, more preferably 1 part by mass or more, based on 100 parts by mass of the total of the aromatic polycarbonate resin (A) and the other resin and/or elastomer. It is greater than or equal to 2 parts by mass, particularly preferably greater than or equal to 3 parts by mass. In addition, the amount of the fluidity improving agent (B) is preferably 25 parts by mass or less based on 100 parts by mass of the total of the aromatic polycarbonate resin (A) and the other resin and/or the elastomer. More preferably, it is 15 parts by mass or less, and particularly preferably 10 parts by mass or less.

[Light diffusing agent (C)]

The light diffusing agent (C) is a fine particle having light diffusing energy. Examples of such fine particles include inorganic fine particles and polymer fine particles.

Examples of the inorganic fine particles include a glass filler, calcium carbonate, barium carbonate, cerium oxide, talc, mica, apatite, and titanium oxide. Among them, preferred is calcium carbonate.

The shape of the inorganic fine particles is preferably granular (including amorphous) or plate-like as compared with the fibrous form. For example, in the case of the glass filler, glass beads, glass spheres, glass-ground fibers, glass sheets, extremely thin glass sheets (manufactured by a sol-gel method), amorphous glass, and the like can be cited. Other inorganic fine particles can also take a variety of shapes.

The inorganic fine particles may be subjected to surface treatment using various fluorenone compounds such as a decane coupling agent or a polyorganometallic hydroquinone compound, a fatty acid ester compound, an olefin compound or the like. The surface-treated inorganic fine particles are effective for improving thermal stability and hydrolysis resistance.

The refractive index of the inorganic fine particles is preferably 1.4 to 1.8. When the refractive index of the inorganic fine particles is in this range, both the light diffusibility and the total light transmittance are good. The refractive index of the inorganic fine particles is well known in various literatures, and can be easily measured by a liquid immersion method or the like.

In view of the light diffusibility, the polymer microparticles are preferably spherical, and the closer to the spherical shape, the better.

Examples of the polymer fine particles include organic crosslinked particles obtained by polymerizing a non-crosslinkable monomer and a crosslinkable monomer; an anthrone-based crosslinked particle; and an amorphous heat-resistant polymer such as a polyether ruthenium particle. Particles; epoxy resin particles, polyurethane resin particles, melamine resin particles, benzoguanamine resin particles, phenol resin particles, and the like. In the case of the amorphous heat-resistant polymer particles, when the aromatic polycarbonate-based resin (A) is kneaded while heating, the form of the particles is not impaired, so that a cross-linkable monomer is not necessarily required. Among these polymer microparticles, organic crosslinked particles are particularly preferred.

Examples of the non-crosslinkable monomer used in the organic crosslinked particles include non-crosslinkable vinyl monomers such as acrylic monomers, styrene monomers, and acrylonitrile monomers; and olefin monomers; Wait.

Examples of the acrylic monomer include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, and propyl methacrylate. Butyl methacrylate, 2-ethylhexyl methacrylate, and phenyl acrylate. Among them, methyl methacrylate is particularly preferred.

Examples of the styrene-based monomer include alkylstyrene such as styrene, α-methylstyrene, methylstyrene (vinyltoluene), and ethylstyrene; halogenated styrene such as brominated styrene; and the like. . Among them, styrene is particularly preferred.

Examples of the acrylonitrile-based monomer include acrylonitrile and methacrylonitrile.

Examples of the olefin-based monomer include ethylene and various norbornene-type compounds.

Examples of other copolymerizable monomers include glycidyl methacrylate, n-methyl maleimide, and maleic anhydride. As a result, the organic crosslinked particles may also have units such as n-methylpentamethyleneimine.

These monomers may be used alone or in combination of two or more.

Examples of the crosslinkable monomer used in the organic crosslinked particles include divinylbenzene, allyl methacrylate, triallyl cyanurate, triallyl isocyanate, and ethylene glycol. (Meth) acrylate, diethylene glycol di(meth) acrylate, propylene glycol (meth) acrylate, 1,6-hexanediol di(meth) acrylate, trimethylolpropane (methyl Acrylate, pentaerythritol tetra(meth)acrylate, bisphenol A di(meth)acrylate, dicyclopentanol di(meth)acrylate, dicyclopentenyl di(meth)acrylate, and positive Hydroxymethyl (meth) acrylamine and the like.

Examples of the method for producing the organic crosslinked particles include an emulsion polymerization method, a suspension polymerization method, a soap-free polymerization method using an initiator such as potassium persulfate, a seed polymerization method, and a two-stage swelling polymerization method. Further, as the suspension polymerization method, a method of separately maintaining the aqueous phase and the monomer phase and supplying both of them to the continuous dispersing machine, and controlling the particle diameter according to the number of rotations of the dispersing machine may be employed; In the continuous production method, the monomer phase is supplied and controlled by a fine-diameter orifice or a porous filter of several to several tens of μm in an aqueous liquid having a dispersing energy.

The anthrone-based crosslinked particle system has a higher degree of crosslinking represented by polymethylsilsesquioxane, and a methyl hydrazine, which has a higher degree of crosslinking represented by polymethylsilsesquioxane as a main skeleton and an organic substituent in a ruthenium atom. The ketone rubber particles are represented by those having a lower degree of crosslinking. In the present invention, it is preferred that the degree of crosslinking represented by polymethylsilsesquioxane is higher.

Examples of the organic substituent bonded to the fluorene atom of the fluorenone-based crosslinked particles include an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group; an aryl group such as a phenyl group; and an aralkyl group such as a benzyl group. Carboxylic acid, hydroxyl group, ester group, ether group, and the like.

Examples of the method for producing the fluorenone-based crosslinked particles include a method of hydrolyzing and condensing a trifunctional alkoxysilane in water to form a siloxane to form a three-dimensional cross-linking. particle.

The particle diameter of the fluorenone-based crosslinked particles can be controlled depending on the amount of the base as a catalyst, the stirring conditions, and the like.

Examples of the method for producing the polymer fine particles include a spray drying method, a liquid solidification method (solidification method), a phase separation method (core material separation method), a solvent evaporation method, and a reprecipitation method. Further, in these methods, a nozzle vibration method or the like may be used in combination.

Examples of the structure of the polymer fine particles include a single-phase structure, a core-shell structure, and a network interpenetrating interchain (IPN) structure in which two or more kinds of components are entangled with each other. Further, it may be a composite particle in which inorganic fine particles are used as a core and components of organic crosslinked particles are used as a shell, and organic crosslinked particles are used as a core, and an epoxy resin or a polyurethane resin is used as a composite of shells. Type particles, etc.

The refractive index of the polymer microparticles is usually about 1.33 to 1.7. When the refractive index of the polymer fine particles is within this range, a sufficient light diffusing function can be exhibited in the state of being added to the resin composition.

As the light diffusing agent (C), the polymer fine particles are preferable to the inorganic fine particles. By using polymer microparticles, both light diffusivity and total light transmittance can be increased to a higher level. In general, the polymer fine particles have a smaller effect of improving the rigidity and dimensional stability of the molded article than the inorganic fine particles. However, the aromatic polycarbonate resin composition of the present invention can be improved by combining with other components. The rigidity and dimensional stability of the molded article make it possible to use polymer microparticles with confidence.

The average particle diameter of the light diffusing agent (C) is preferably from 0.01 to 50 μm, more preferably from 0.1 to 10 μm, particularly preferably from 0.1 to 8 μm. The average particle diameter can be expressed by 50% (D50) of the integrated distribution of the particle sizes obtained by the laser light scattering method.

The light diffusing agent (C) preferably has a narrow particle size distribution, and more preferably has a particle size distribution in which the average particle diameter is in the range of ±2 μm, which is 70% by mass or more.

The refractive index of the light diffusing agent (C), that is, the absolute value of the difference between the refractive index of the aromatic polycarbonate resin (A) and the refractive index of the aromatic polycarbonate resin (A) is preferably 0.02 to 0.2. Since the difference in refractive index is in this range, both light diffusibility and total light transmittance can be increased to a higher level. The refractive index of the light diffusing agent (C) is preferably lower than the refractive index of the aromatic polycarbonate resin (A).

The addition amount of the light-diffusing agent (C) is preferably 0.1 to 100 parts by mass of the total of the aromatic polycarbonate-based resin (A) and the other resin and/or the elastomer and the fluidity improver (B). 30 parts by mass, more preferably 0.3 to 20 parts by mass, particularly preferably 0.4 to 15 parts by mass, particularly preferably 0.5 to 10 parts by mass. When the amount of the light diffusing agent (C) added is in this range, the high light diffusing function can be exhibited.

[Other additives]

In the aromatic polycarbonate-based resin composition of the present invention, a flame retardant (for example, a brominated epoxy resin or a brominated polystyrene) may be added as needed within a range not impairing the object and effect of the present invention. , brominated polycarbonate, brominated polyacrylate, monophosphate compound, phosphate oligomer compound, phosphonate oligomer compound, phosphazene oligomer compound, phosphonium amide compound, organic sulfonate base Metal salt, organic sulfonate alkaline earth metal salt, fluorenone flammable agent, etc.), flame retardant aid (for example, sodium citrate, antimony trioxide, etc.); anti-drip agent (having a mixture of fibrous formation energy) Tetrafluoroethylene, etc., antioxidants (for example, hindered phenolic compounds, sulfur-based antioxidants, etc.), ultraviolet absorbers, light stabilizers, mold release agents, slip agents, dyes, antistatic agents, inorganic or organic antibacterial agents Photocatalyst antifouling agents (particulate titanium oxide, fine particle zinc oxide, etc.), infrared absorbing agents, sensitizers, and fluorescent whitening agents.

The aromatic polycarbonate-based resin composition of the present invention preferably contains a phosphorus-containing heat stabilizer. Examples of the phosphorus-containing heat stabilizer include phosphates such as trimethyl phosphate; triphenyl phosphate, tridecyl phenyl phosphate, distearyl ester pentaerythritol diphosphate, and bis (2, 6-di). -T-butyl-4-methylphenyl)pentaerythritol diphosphate, tris(2,4-di-t-butylphenyl)phosphate, 2,2-methylenebis(4,6-di a phosphite such as t-butylphenyl)octyl phosphate or bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphate; tetrakis(2,4-di-t-butyl) A phosphonite such as phenyl)-4,4'-biphenyldiphosphonate. The content of the phosphorus-containing heat stabilizer is preferably 0.001 to 1% by mass, more preferably 0.01 to 0.5% by mass, particularly preferably 0.01%, based on the aromatic polycarbonate resin composition (100% by mass). 0.2% by mass. By adding a phosphorus-containing heat stabilizer, the thermal stability of the aromatic polycarbonate-based resin composition can be further improved, and favorable molding process characteristics can be obtained.

[Preparation of Aromatic Polycarbonate Resin Composition]

The method for producing the aromatic polycarbonate-based resin composition of the present invention includes, for example, a method in which an aromatic polycarbonate-based resin (A), a fluidity improver (B), and a light-diffusing agent are mixed in advance ( C) Other components may be mixed in advance as needed, and thereafter melt-kneaded and granulated.

Examples of the apparatus for premixing include a conical spiral mixer, a V-type agitator, a Henschel mixer, a mechanochemical device, an extrusion mixer, and the like. In the premixing, granulation may be carried out by extruding a granulator, a compression solidification machine or the like depending on the case.

Examples of the apparatus for melt kneading include a melt kneading machine such as a tuyere type two-axis extruder, a Banbury kneading machine, a kneading drum, and a constant heat stirring container. Among them, a multi-axis extruder such as a tuyere type two-axis extruder is preferable.

As a device for granulation, a granulator etc. are mentioned.

Examples of the method of melt-kneading include (i) a method in which an aromatic polycarbonate-based resin (A), a fluidity improver (B), and a light-diffusing agent (c) are simultaneously kneaded; (ii) a predetermined preparation in an aromatic The clinker of the light diffusing agent (C) is added to a part of the polycarbonate resin (A), and is supplied together with the remaining aromatic polycarbonate resin (A) and the fluidity improver (B). The method of melt-kneading after the extruder is taken out. The method (ii) is carried out for the purpose of ensuring measurement accuracy because the light diffusing agent (c) is relatively small. Among them, the method of (i) is preferred.

The aromatic polycarbonate-based resin composition of the present invention can be used for molding by an injection molding method, an extrusion molding method, or the like. Thereby, fluidity at the time of molding can be improved, and a molded article having high heat resistance, chemical resistance, transparency, and light diffusibility can be obtained.

In these molding fields, particularly in the field of injection molding, it is strongly desired to improve the fluidity at the time of forming a resin composition. Therefore, it is possible to obtain a large usefulness by applying the polycarbonate resin composition of the present invention.

Moreover, since the light-diffusing aromatic polycarbonate-based resin composition of the present invention is often used for a molded article requiring high optical characteristics, it is preferred to reduce the amount of foreign matter that may impair optical characteristics. Therefore, a raw material having a small amount of foreign matter can be used, and a manufacturing apparatus such as an extruder or a granulator can be installed in a clean air atmosphere, and for the cooling water for the cooling tank, a foreign matter can be used less, and thus It is good that the raw material supply funnel, the supply flow path, the particle storage tank, and the like are also filled with clean air. For example, the same method as that disclosed in Japanese Laid-Open Patent Publication No. Hei 11-21357 can be employed.

[Light diffusion molded product]

The light-diffusing molded article of the present invention can be obtained by melt-molding the aromatic polycarbonate-based resin composition of the present invention by a well-known melt molding method.

As the melt molding method, an injection molding method is preferred. Examples of the injection molding method include a general injection molding method, and an injection compression molding method, an injection compression molding method, a gas-assisted injection molding method, and a foam molding method (including those obtained by injecting a supercritical fluid). Insert molding method, in-mold coating molding method, heat-dissipating mold forming method, rapid heating and cooling mold forming method, two-color molding method, sandwich molding method, and ultra-high-speed injection molding method. The advantages of these forming methods are well known. The forming can be a cold runner method or a hot runner method.

By using the extrusion molding method as the melt molding method, various shaped extrusion molded articles, sheets, films, and the like having a light diffusion function can be produced. For the production of a thin plate or a film, an expansion method, a calender method, a casting method, or the like can also be used. Further, a heat shrinkable tube can be produced by performing a specific stretching treatment on the thin plate or the film. Further, a hollow molded article can be produced by spin molding, blow molding, or the like.

Examples of the light-diffusing molded article of the present invention include a light diffusing plate, a light diffusing film, and an electron. Electrical equipment, OA machine parts, vehicle parts, mechanical parts, agricultural materials, fishery materials, transport containers, packaging containers, and miscellaneous goods. Specific examples include a light diffusing plate for an image display device (a light diffusing plate for a backlight module such as a liquid crystal display device, a light diffusing plate for a projection type display such as a projection television), and image reading. A light diffusing plate, a lamp cover, a measuring instrument, a kanban (especially an internal type), a resin window glass, a roof material for a ship, a ceiling material for a ship, a ceiling material for a house, a solar cell cover, and the like are used for the device. As the backlight module of a liquid crystal display device or the like, various light sources (cold cathode tubes, LEDs, etc.) can be used.

The aromatic polycarbonate-based resin composition of the present invention is suitable for use in the production of a large-sized and thin light-diffusing sheet (particularly, a light-diffusing sheet for an image display device). According to the aromatic polycarbonate-based resin composition of the present invention, a light-diffusing sheet having a surface area of 500 to 50,000 cm ² can be obtained. Preferably, the light diffusing plate has a surface area of 1000 to 25,000 cm ² and a preferred thickness of 0.3 to 3 mm. As described above, the aromatic polycarbonate-based resin composition of the present invention can produce a light-diffusing sheet which is large in size, high in dimensional stability, and thin (lightweight).

The light diffusing plate may be a single layer plate having a surface shape such as a Fresnel lens shape or a cylindrical lens shape, or may be laminated on a light diffusing plate with other materials having a surface shape such as a Fresnel lens shape or a cylindrical lens shape. Laminated board.

The single-layered plate having a surface shape such as a Fresnel lens shape or a cylindrical lens shape can be formed into an aromatic polycarbonate resin composition of the present invention by an injection molding method, a compression molding method, an extrusion molding method, or the like. The manufacturer's desired shape is manufactured. As a method of forming a Fresnel lens shape (concavo-convex shape) on the surface, (i) a concave-convex corresponding to the shape of the Fresnel lens is provided on the surface of the mold cavity or the surface of the transfer roller, and is formed on the surface of the molded article. a method of transferring the unevenness; (ii) inserting another material having a concave-convex corresponding to the shape of the Fresnel lens into the cavity of the mold, or laminating by extrusion molding, and integrating the other material with the molded article; A method of transferring unevenness on the surface of a molded article by removing other materials.

Moreover, the uneven shape of the Fresnel lens shape or the like can be omitted by laminating a layer containing a bright pigment in the light diffusing plate. Further, the light diffusing plate for an image display device may be formed by preventing light rays from the light source from being reflected on the side surface of the light source (the surface opposite to the observer) to form various light reflection preventing films.

Since the light-diffusing molded article of the present invention is excellent in chemical resistance, it can be subjected to surface modification, and as a result, other functions can be imparted. "surface modification", that is, light diffusion molding by vapor deposition (physical vapor deposition, chemical vapor deposition, etc.), electroplating (electrical plating, electroless plating, melt plating, etc.), coating, coating, and printing. Set a new layer on the surface of the product.

As the surface modification method, a well-known surface modification method used in a general resin molded article can be mentioned.

Examples of the surface modification method in which a metal layer or a metal oxide layer is provided on the surface of the light-diffusing molded article include a vapor deposition method (physical vapor deposition method and chemical vapor deposition method), a spray method, and a plating method. Examples of the physical vapor deposition method include a vacuum deposition method, a sputtering method, and an ion plating method. Examples of the chemical vapor deposition (CVD) method include a thermal CVD method, a plasma CVD method, and a photo CVD method. Examples of the spray method include an atmospheric piezoelectric slurry spray method and a reduced pressure plasma spray method. Examples of the plating method include electroless plating (chemical plating), melt plating, and electroplating. As the electroplating method, a laser plating method can be cited.

In the case of the surface modification method, when a metal layer is provided on the surface of the light-diffusing molded article, it is preferably a vapor deposition method or a plating method, in the case where a metal oxide layer is provided on the surface of the light-diffusing molded article. Preferably, the evaporation method is used. The vapor deposition method and the plating method can also be used in combination. For example, the following method or the like can be employed: electrical plating is performed using a metal layer formed by a vapor deposition method.

[Examples]

Hereinafter, the present invention will be described in further detail by way of examples. In the following, "parts" and "%" indicate "parts by mass" and "% by mass" unless otherwise specified.

(Manufacturing Example 1)

Manufacture of fluidity improver (B-1): In a separable flask equipped with a cooling tube and a stirring device, (solid content 28%) 1.0 part (solid content) anionic emulsifier ("Lat Mulu ASK") 295 parts of distilled water, and heated to 80 ° C in a water bath under a nitrogen atmosphere. Then, in a separable flask, 0.0001 part of monovalent iron sulfate, 0.0003 part of ethylene diamine tetraacetic acid disodium salt, and 0.3 part of rongalite are dissolved in 5 parts of distilled water, and then, the following is added dropwise. Mixture: 87.5 parts of styrene, 12.5 parts of phenyl methacrylate, 0.2 part of a third butyl hydroxy peroxide, and 0.5 parts of n-octyl thiol for 180 minutes. Thereafter, the mixture was stirred at 80 ° C for 60 minutes to obtain a polymer latex (polymerization ratio: 98%).

300 parts of an aqueous solution of sulfuric acid dissolved in a ratio of 0.7% was stirred, and the mixture was heated to 70 ° C, and after slowly dropping the obtained polymer latex, the polymer was solidified. After separating the precipitate and washing it, it was dried at 75 ° C for 24 hours to obtain a polymer (fluidity improver (B-1)). The weight average molecular weight (Mw) was 49,000, and the molecular weight distribution (Mw/Mn) was 2.1.

(Manufacturing Example 2)

Production of fluidity improver (B-2): A polymer (fluidity improver (B-) was obtained according to the same method as in Production Example 1, except that the amount of n-octyl mercaptan was changed from 0.5 part to 0.2 part. 2)) (Polymerization rate: 98%). The weight average molecular weight (Mw) was 97,000, and the molecular weight distribution (Mw/Mn) was 2.0.

(Manufacturing Example 3)

Production of fluidity improver (B-3): In addition to styrene 20 parts, phenyl methacrylate 80 parts, n-octyl mercaptan amount changed from 0.5 parts to 2 parts, other basis and manufacture In the same manner as in Example 1, a polymer (fluidity improver (B-3)) (polymerization rate: 99%) was obtained. The weight average molecular weight (Mw) was 27,000, and the molecular weight distribution (Mw/Mn) was 1.9.

(Manufacturing Example 4)

Manufacture of fluidity improver (B'-4): In a separable flask with a cooling tube and a stirring device, 0.4 parts of calcium phosphate, 150 parts of distilled water, followed by the addition of 96 parts of styrene and 4 parts of methacrylic acid were added. A mixture of n-butyl ester and 1.2 parts of benzamidine benzoate was stirred for a while and nitrogen foaming was carried out for 30 minutes. The mixture was stirred at 80 ° C for 4 hours under a nitrogen atmosphere, and further stirred at 90 ° C for 1 hour. After separating and washing the precipitate, it was dried at 75 ° C for 24 hours to obtain a polymer (fluidity improver (B'-4)) (polymerization ratio: 97%). The weight average molecular weight (Mw) was 150,000, and the molecular weight distribution (Mw/Mn) was 3.3.

The amounts (parts), the polymerization pattern, the polymerization ratio, the weight average molecular weight (Mw) of the obtained polymer, and the molecular weight distribution (Mw/Mn) of the respective components in Production Examples 1 to 4 are shown in Table 1. Further, in the table, St is styrene, PhMA is phenyl methacrylate, BA is n-butyl acrylate, and BPO is benzoyl peroxide. Further, the polymerization ratio was calculated from the mass of the solid matter of the obtained polymer. Further, the weight average molecular weight (Mw) and the number average molecular weight (Mn) were measured by a GPC method (elution liquid: chloroform).

(Examples 1 to 4, Comparative Examples 1 to 3)

The following is prepared as an aromatic polycarbonate resin.

PC1: an aromatic polycarbonate resin, "PANLITE L1225WS", manufactured by Teijin Chemicals Co., Ltd., having a viscosity average molecular weight of 21,000.

PC2: an aromatic polycarbonate resin, "PANLITE L1225ZL", manufactured by Teijin Chemicals Co., Ltd., having a viscosity average molecular weight of 18,000.

The fluidity improver and the aromatic polycarbonate-based resin were mixed in an amount shown in Table 2 (total of 100 parts), and further 0.7 parts of a light-diffusing agent (bead-shaped cross-linked fluorenone particles "Amnesia 120" was added. , average particle diameter: 2 μm, manufactured by GE Toshiba Ketone Co., Ltd., 0.3 parts of UV absorber ("TINUVIN 329", manufactured by CIBA Specialty Chemicals Co., Ltd.), 0.1 part of antioxidant ("Irganoxs 1076", CIBA Specialty Chemicals 0.1% of the heat stabilizer ("ADK STAB 2112", manufactured by Asahi Kasei Kogyo Co., Ltd.), and supplied to a two-axis extruder (model name "TEM-35", manufactured by Toshiba Machine Co., Ltd.) The mixture was melt-kneaded at 280 ° C to obtain an aromatic polycarbonate-based resin composition.

The following aromatic polycarbonate resin compositions were evaluated for the following (1) to (6). The results are shown in Table 2.

(evaluation method)

(1) Melt fluidity: The spiral fluidity length (SFL) of the aromatic polycarbonate resin composition was evaluated using an injection molding machine ("IS-100", manufactured by Toshiba Machine Co., Ltd.). The molding temperature was set to 280 ° C, the mold temperature was set to 80 ° C, and the injection pressure was set to 98 MPa. Further, the thickness of the molded article was set to 2 mm and the width was set to 5 mm.

(2) Drug resistance: A laminate having a thickness of 2 mm and a size of 15 cm was produced by an injection molding machine ("IS-100", manufactured by Toshiba Machine Co., Ltd.) using an aromatic polycarbonate resin composition. After the cutting, a light-diffusing molded article having a thickness of 2 mm and a thickness of 15 cm × 2.5 cm was obtained. The test piece was annealed at 120 ° C for 2 hours, and then subjected to a cantilever test to measure the breaking time of the test piece after the drug was applied. The measurement was carried out at a test temperature: 23 ° C, a load: 20 MPa, and a solvent: toluene / isooctane = 1 / 1 vol ratio.

(3) Surface peeling property (peeling resistance): The protruding pin traces of the light-diffusing molded article obtained in (2) were slit with a cutter, and the peeling state was visually observed. The evaluation criteria are as follows.

○: No peeling is good.

X: Surface peeling can be seen.

(4) Load bending temperature (heat resistance): An aromatic polycarbonate resin composition was used to form a thickness of 1/4 inch by an injection molding machine ("IS-100", manufactured by Toshiba Machine Co., Ltd.). The light diffuses the molded article. The load bending temperature of the light-diffusing molded article was measured in accordance with ASTM D648. The annealing treatment was carried out at 120 ° C for 1 hour, and the load was set to 1.82 MPa.

(5) Total light transmittance: An aromatic polycarbonate resin composition was used to form a light having a thickness of 2 mm and a thickness of 15 cm by an injection molding machine ("IS-100", manufactured by Toshiba Machine Co., Ltd.). Diffusion molded product. The total light transmittance of the light-diffusing molded article was measured at 23 ° C using ASTM D1003 as a standard.

(6) Light diffusibility: A backlight unit including a cold cathode tube was placed under the light-diffusing molded article obtained in (5), and a light-diffusing molded article was observed from the upper side to evaluate light uniformity. Those with good uniformity were set to ○, and those with poor uniformity were set to ×.

As is apparent from the results of Table 2, the aromatic polycarbonate-based resin compositions obtained in Examples 1 to 4 have remarkably improved fluidity, and the light-diffusing molded article does not impair light diffusibility, heat resistance, and peeling resistance. And the drug resistance is significantly improved, and the physical balance is very good.

On the other hand, the aromatic polycarbonate-based resin composition obtained in Comparative Example 1 had insufficient compatibility, and thus the light-diffusing molded article could not obtain good peeling resistance, and the light diffusibility was also insufficient.

In addition, the light-diffusing aromatic polycarbonate-based resin composition obtained in Comparative Examples 2 and 3 does not contain a fluidity improver, and thus sufficient fluidity and chemical resistance cannot be obtained.

(Examples 5 to 12, Comparative Examples 4 to 7)

The following is prepared as an aromatic polycarbonate resin.

PC3: an aromatic polycarbonate resin, "PANLITE L1225LL", manufactured by Teijin Chemicals Co., Ltd., having a viscosity average molecular weight of 15,000.

The following is prepared as a light diffusing agent.

C-1: bead-shaped crosslinked fluorenone particles "Amoy Pall 120", average particle diameter: 2 μm, GE Toshiba Ketone Co., Ltd. C-2: beaded crosslinked propylene particles "MB30X-5", C-3: beaded crosslinked propylene particles "EXL-5136", average particle diameter: 8 μm, manufactured by ROHMHAAS Co., Ltd.

The aromatic polycarbonate resin, the fluidity improver, and the light diffusing agent are mixed in an amount shown in Table 3 (a total of 100 parts of the aromatic polycarbonate resin and the fluidity improver), and further 0.3 parts of ultraviolet rays are added. Absorbent ("TINUVIN 329", manufactured by CIBA Specialty Chemicals Co., Ltd.), 0.1 part of antioxidant ("Irganoxs 1076", manufactured by CIBA Specialty Chemicals Co., Ltd.), 0.1 part of heat stabilizer ("ADK STAB 2112", Asahi Kasei Industrial Co., Ltd. was supplied to a two-axis extruder (model name "TEM-35", manufactured by Toshiba Machine Co., Ltd.), and melt-kneaded at 280 ° C to obtain an aromatic polycarbonate-based resin composition.

The following aromatic polycarbonate resin composition was evaluated for the following (1) to (3). The results are shown in Table 3.

(evaluation method)

(1) Melt fluidity: The spiral fluidity length (SFL) of the aromatic polycarbonate resin composition was evaluated using an injection molding machine ("IS-100", manufactured by Toshiba Machine Co., Ltd.). The molding temperature was 280. °C, the mold temperature was set to 80 ° C, and the injection pressure was set to 98 MPa. Further, the thickness of the molded article was set to 2 mm and the width was set to 15 mm.

(2) Total light transmittance: An aromatic polycarbonate resin composition was used, and it was formed into a thickness of 2 mm and 5 cm × 10 cm by an injection molding machine ("IS-100", manufactured by Toshiba Machine Co., Ltd.). See Fang Guangguang Diffusion Molding. The total light transmittance of the light-diffusing molded article was measured at 23 ° C using ASTM D1003 as a standard.

(3) Diffusion rate: The diffusivity of the light-diffusing molded article obtained in (2) was measured at 23 ° C using DIN 5036 as a standard.

As is apparent from the results of Table 3, the aromatic polycarbonate-based resin compositions obtained in Examples 5 to 12 have remarkably improved fluidity, and the light-diffusing molded article is excellent in the balance of total light transmittance and diffusivity.

On the other hand, the light-diffusing aromatic polycarbonate-based resin composition obtained in Comparative Examples 4 to 7 does not contain a fluidity improver, and thus sufficient fluidity cannot be obtained.

[Industrial availability]

The aromatic polycarbonate-based resin composition of the present invention does not impair the excellent properties (light diffusibility, heat resistance, impact resistance, dimensional stability, etc.) of the obtained light-diffusing molded article, and melt fluidity (forming Sex) and drug resistance are improved. Therefore, the light-diffusing molded article containing the aromatic polycarbonate-based resin composition of the present invention is excellent in light diffusibility, chemical resistance, and the like, and can be increased in size, thickness (light weight), and complicated in shape. And high performance, in particular, it can be applied to a light diffusing plate for a large and thin image display device (for example, a light diffusing plate for a backlight module such as a liquid crystal display device, or a projection type display for a projection television) A light-diffusing sheet of a device display screen or the like, a high-performance light-diffusing film (for example, a high-transmitting light-diffusing film for improving the brightness of a liquid crystal display device or the like) by surface processing such as printing. Further, the light-diffusing molded article of the present invention can be used for, for example, a lamp cover, a gauge, a kanban (especially an internal illumination type), a resin window glass, and the like, in addition to a light diffusion plate and a light diffusion film for an image display device. Light diffusing plate for reading device, roofing material for vehicles, ceiling material for ships, roofing materials for residential use, solar battery cover, electrical. Electronic equipment parts, OA machine parts, vehicle parts, mechanical parts, agricultural materials, fishery materials, transport containers, packaging containers, and groceries are extremely high in industrial value.

While the present invention has been described in its preferred embodiments, the present invention is not intended to limit the invention, and the present invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the definition of the scope of the patent application.

Claims (5)

An aromatic polycarbonate-based resin composition to which an aromatic polycarbonate-based resin (A), a fluidity improver (B), and a light-diffusing agent (C) are added, and the fluidity improver (B) is polymerized 50 to 99.5% by mass of the aromatic vinyl monomer (b1), 0.5 to 50% by mass of the monomer (b2) represented by the following formula (I), and 0 to 40% by mass of the other monomer ( B3) A polymer obtained by mixing a monomer mixture, wherein the monomer (b1) to the monomer (b3) are 100% by mass in total: In the formula (I), R ¹ is a hydrogen atom or a methyl group, and R ² is a phenyl group which may have a substituent. The aromatic polycarbonate-based resin composition according to the first aspect of the invention, wherein the aromatic polycarbonate-based resin (A) has a viscosity average molecular weight of from 12,000 to 40,000. The aromatic polycarbonate-based resin composition according to the first aspect of the invention, wherein the fluidity-improving agent (B) has a weight average molecular weight of 5,000 to 200,000. The aromatic polycarbonate-based resin composition according to claim 1, which is used for injection molding. A light diffusing molded article which is the first item of the patent application scope The aromatic polycarbonate resin composition described above is molded.